4.4.3邻接表的广度优先遍历

#include <bits/stdc++.h>
#include "Graph.cpp"

using namespace std;

void BFS(ALGraph *G, int v) { // 邻接表的BFS算法
	ArcNode *p;
	int w;
	int visited[MAXV];
	queue<int> qu; // 定义存放访问过的顶点的标志数组
	memset(visited, 0, sizeof(visited)); // 初始化访问标志数组
	cout << v << " ";
	visited[v] = 1;
	qu.push(v); // 访问过的顶点进队
	while(!qu.empty()) {
		w = qu.front();
		qu.pop(); // 出队顶点w
		p = G->adjlist[w].firstarc; // 找到顶点w的第一个邻接点
		while(p != NULL) {
			if(visited[p->adjvex] == 0) {
				cout << p->adjvex << " ";
				visited[p->adjvex] = 1;
				qu.push(p->adjvex);
			}
			p = p->nextarc; // 找到顶点w的下一个邻接点
		}
	}
	cout << endl;
}

int main() {
	ALGraph *G;
	int A[][MAXV]= {
		{0,1,0,0,1},
		{0,0,1,1,1},
		{0,0,0,0,0},
		{0,0,1,0,1},
		{0,0,0,0,0}
	};
	int n=5,e=7;
	CreateAdj(G, A, n, e); //创建图的邻接表存储结构G
	cout << "图的邻接表如下：" << endl;
	DispAdj(G);
	cout << "图的邻接表的广度优先遍历如下：" << endl; 
	BFS(G, 0); 
	return 0;
}

#include <bits/stdc++.h>
#define MAXV 50 // 最大顶点个数
#define MAXL 20
#define INF 0x3f3f3f3f  //表示∞ 

using namespace std;

typedef struct ANode {
	int adjvex; // 该边的终点编号
	int weight; // 改变的权值
	struct ANode *nextarc; //指向下一条边的指针
} ArcNode; // 边结点的类型

typedef struct Vnode {
	char data[MAXL]; // 顶点信息
	ArcNode *firstarc; // 指向第一条边
} VNode; // 邻接表的表头的结点类型

typedef VNode AdjList[MAXV]; // AdjList是邻接表类型

typedef struct {
	AdjList adjlist; // 邻接表
	int n, e; // 图中的顶点数和边数
} ALGraph; // 图

void CreateAdj(ALGraph *&G, int A[][MAXV], int n, int e) { //建立图的邻接表
	ArcNode *p;
	G = (ALGraph *) malloc (sizeof(ALGraph));
	G->n = n;
	G->e = e;
	for(int k = 0; k < n; k++)
		G->adjlist[k].firstarc = NULL;
	for(int i = 0; i < n; i++)
		for(int j = 0; j < n; j++)
			if(A[i][j] != 0 && A[i][j] != INF) {
				p = (ArcNode *) malloc (sizeof(ArcNode));
				p->adjvex = j;
				p->weight = A[i][j];
				p->nextarc = G->adjlist[i].firstarc;
				G->adjlist[i].firstarc = p;
			}
}

void DispAdj(ALGraph *G) {
	ArcNode *p;
	for(int i = 0; i < G->n; i++) {
		cout << i;
		p = G->adjlist[i].firstarc;
		while(p != NULL) {
			cout << "->" << "结点编号：" << p->adjvex << " 边的权值：" << p->weight;
			p = p->nextarc;
		}
		cout << "^" << endl;
	}
}

void DestroyAdj(ALGraph *&G) { // 销毁图的邻接表
	ArcNode * pre ,*p;
	for(int i = 0; i < G->n; i++) {
		pre = G->adjlist[i].firstarc;
		while(pre != NULL) {
			p = pre->nextarc;
			free(pre);
			pre = p;
		}
	}
	free(G);
}